Drillpro Pressure Gauge Counter Marine Plunger Valve Barometer For Inflatable Boat Raft Barometers small size, easy to carry; Any time check the airbag pressure drop change, identify potential problems in rubber boats; For most rubber boats. Size: 60 * 32mm , Thread Size: 3/8 ", Interface: 18mm (OD), 15mm (ID) Material: Plastic, Silicone